1. The city of Vesali was afflicted by a famine, decaying corpses, and pestilence, so citizens sought help from the Buddha.
2. The Buddha and monks arrived and their presence brought rain that washed away corpses, purifying the city. The Buddha gave a discourse called the Ratana Sutta to protect people.
3. The discourse praises the Buddha, Dhamma, and Sangha as the three jewels and describes their qualities, like the Buddha realizing cessation and the path to peace. Chanting it exorcised spirits and ended the pestilence.